Novel contribution to the taxonomy and molecular phylogeny of scuticociliates (Protozoa): Resolving the non-monophyly of the genus Paranophrys Thompson and Berger, 1965 and the establishment of the genus Anteparanophrys n. Gen

J Invertebr Pathol. 2025 Jan 4:108267. doi: 10.1016/j.jip.2025.108267. Online ahead of print.

Abstract

During a field survey of parasitic ciliates diversity in South Korea, a scuticociliate was found in a water sample collected during scuba diving. At first glance, the species looks similar to members of the genus Paranophrys especially P. magna but they differ mainly in the body size and the number of somatic kineties. Thus, integrative taxonomic approaches (i.e., silver impregnations, scanning electron microscopy, and molecular phylogeny) were applied and confirmed that the isolate is a new species. Detailed comparison between the new species and the three members of the genus Paranophrys revealed that the new species is similar to P. magna in having membranelle 1 slightly shorter than membranelles 2 and the monokinetids are randomly scattered between dikinetids within each somatic kinety. On the other hand, membranelle 1 in both P. marina, the type species of the genus, and P. thompsoni, is about three times longer than membranelle 2 and their ciliary rows invariably consist of dikinetids anteriorly and monokinetids posteriorly. Observations on the feeding behavior and habitat suggest that the new species is facultative histophagous. Phylogenetic analyses based on 18S rRNA gene indicate that the new species and P. magna belong to the newly established genus Anteparanophrys n. gen. i.e., Anteparanophrys koreana n. sp. and Anteparanophrys magna (Borror, 1972) n. comb.

Keywords: Anteparanophrys magna (Borror, 1972) n. comb.; COI gene; Marine habitat; Morphology; Phylogeny.